In data center environments, rack units may house many server devices. Each server device may be configured to host one or more virtual host (virtual machine) devices. The servers in the rack units are connected to top-of-rack (ToR) leaf switch devices. The leaf switches, in turn, are connected to other leaf switches via one or more spine switches to form a layer 3 distributed fabric. Network switches form a physical underlay network, which may be used by multiple tenant overlay networks that exchange data communications between host devices (physical and/or virtual) in different rack units. For example, packets of data communications may be sent from a virtual machine in one rack unit to a virtual machine in another rack unit. These packets may be routed between corresponding leaf switch devices and the intermediary spine switch. The leaf switches are configured to store address information associated with the host devices in the data center environment. An important aspect of network orchestration is to ensure that multiple physical or virtual hosts do not share the same Internet Protocol (IP) address in a given IP routing domain.